The present invention relates to coin operated locks of the type first described in U.S. Pat. Nos. 3,193,074 and 3,228.506.
In prior commercial coin operated lock units of the type described in these patents, a coin gauging lever is supported on a side wall of the coin chute for pivotal movements between coin gauging and release positions. When in gauging position, the lever cooperates with a front edge of a coin chute or other suitably defined gauging surface to gauge the size of coins deposited in the coin chute and to temporarily support a properly sized coin(s) in a coin sensing position or station, wherein it can be sensed by a coin feeler finger, which thereupon frees a patron key controlled lock for rotation from its unlocked position into its locked position. Rotation of the patron lock into its locked position or subsequent removal of the patron key from the patron lock, which can only occur when the patron lock is in its locked position, frees the coin gauging lever for pivotal movement into a release position permitting the previously sensed coin to fall by gravity into a temporary storage position defined by a coin holding pawl for the case where the lock unit is adjusted to render "free" service or for discharge from the lock unit into a coin collection box for the case where the lock unit is adjusted to render "prepaid" service; in either case the lever thereafter being forced to return to its gauging position as an incident to the return of the patron lock to its unlocked position or reinsertion of the patron key. When the lock unit is adjusted to render "free" service, the coin holding pawl is withdrawn from its operative or coin holding position within the coin chute, as an incident to return of the patron lock into its unlocked position, to allow for discharge of the coin from the temporary storage position for return to a patron via a coin return or discharge slot formed in the front plate of the lock unit.
A drawback of these prior lock units is that when they are adjusted to render "free" service, it is possible to effect withdrawal of the coin holding pawl from the coin chute sufficiently to permit discharge of a coin from its temporary storage position for return to the patron, during an initial stage of unlocking rotary movement of the patron lock, which is completed slightly before the patron lock is rotated through an arc sufficient to render operable a latch mechanism defined by the patron lock and coin gauging lever otherwise serving to prevent return movement of the patron lock to its locked position until another coin is subsequently deposited in the lock unit. As a result, a vandal, after once having had his coin deposit returned, can return the patron lock to locked position and remove the patron key as a trophy. The loss of the patron key renders the locker unusable until such time as a custodian can gain access to the lock unit for purposes of replacement of the patron key/patron lock assembly.